"I'm working 60 to 70 hours a week to reach that, and even that is barely enough," she says. "Frankly I think it's verging on slavery."

Recent studies do show that, among people claiming benefits in Switzerland, a significant number are doing so not because they have no work, but because they are not being paid enough to make ends meet.

This has been a key element in the campaign in favour of a minimum wage, with supporters arguing that the Swiss welfare system is being forced to subsidise businesses which refuse to pay a living wage.

'An own goal'

But business leaders and the Swiss government have been campaigning hard against the proposal.

Higher salaries would mean higher pricesUrs Gfeller, Swiss farmer

They point to Switzerland's low unemployment and high standard of living for the majority as evidence that the Swiss way of doing things is successful, and in no need of change.

"I think it's an own goal, for workers as well as for small companies in Switzerland," says Cristina Gaggini, director of the Geneva office of the Swiss business association, Economiesuisse.

"Studies show that a minimum wage can lead to much more unemployment and poverty than it helps people.

"And for very small companies it would be very problematic to afford such a high salary."

The latest polls suggest almost two-thirds of voters are against the proposal

'We'd go to the wall'

Small businesses, and in particular Swiss farmers, are especially worried that being forced to pay their staff 4,000 francs a month would price their products out of the market.

Organic farmer Urs Gfeller believes he and many others like him risk being put out of business.

"Higher salaries would mean higher prices. People would have to pay more for their vegetables and farm produce," he told Swiss television.

Swiss monthly living costs

One-bed city centre flat: 1,800 francs

Utilities: 100-200 francs

Health insurance: 300-400 francs

Public transport: 50-70 francs

Restaurant meal for two: 100-150 francs

"Then cheaper produce would be imported from other countries, Swiss farmers would be finished - we'd go to the wall."

In fact, most of Switzerland's low-paid workers operate in the service industry, in hotels and restaurants, and the majority are women.

Trade unions point out that the fear over cheaper imports does not really apply to Swiss hotels and restaurants, whose customers might be happy to pay a little bit more in order to know those serving them were being paid a living wage.

Public fury

Swiss business leaders hope their campaign will persuade a majority of voters to reject the minimum wage, but they remain very uneasy at growing public criticism of the way they do things.

A referendum last year, known as the 'fat cats initiative' limited executive bonuses and golden handshakes.

This followed public fury that some business leaders, most notably Swiss bankers, continued to earn huge salaries even as the banks themselves were losing money.

This poster urges voters to reject the minimum wage proposal

Another vote, which was designed to ensure that bosses could earn no more than 12 times the salary of the lowest paid in their company, was narrowly defeated last November.

However, the campaign served to focus attention yet again on the high salaries paid to some chief executives.

So before this Sunday's votes have even been counted, some Swiss businesses are already quietly introducing higher salaries, among them supermarket chain Lidl, with fashion retailer H&M set to follow.

Continuing debate

Meanwhile Switzerland's electrical and mechanical engineering industry has shown it understands that some areas of Switzerland, most notably Geneva and Zurich, have exceptionally high costs of living, and has agreed to regional minimum wages.

The latest opinion polls indicate the 4,000 SFr-a-month proposal may be rejected.

But even if the minimum wage is defeated this time, the debate about fair pay in wealthy Switzerland will not be going away.

Coming soon, there will be a referendum on a guaranteed basic income for all Swiss, whether they work or not.